There are a number to tire pressure monitoring devices and systems presently on the market. Generally the tire pressure monitoring devices are mounted inside the tire. Powering such a device, inside a tire on a rotating wheel, with the vehicle electrical system would be complex and expensive. Therefore, these known tire pressure monitoring devices include batteries for electrical power.
Since these known tire pressure monitoring devices are inside a tire, battery replacement is difficult. A motion sensor can be incorporated into the devices to reduce power consumption and extend battery life. Such a motion sensor can sense tire rotation and turn the tire pressure monitoring device on when the tire rotates above a selected speed.